PHP Loop through an associative array - php

Question

Edited to provide clarifications, based on the comments.
I have a dynamic associative array with keys and values that looks like this:
array: ["apples" => 4 "bananas" => 4 "cherries" => 4 "dates" => 3]
I would like to create another n-sized array (with dynamic n) that will loop through the array in series.
Example:
(if n = 6):
apples, cherries, apples
bananas, dates, bananas
cherries, apples, cherries
dates, bananas
apples, cherries
bananas, dates
n range is between 1 and sum of all values
the code I have so far is this:
function makeArray($commonWords){
$n = 6;
$result = array_fill(0,$n, '');
$i = 0;
while (list($key, $value) = each($commonWords)) {
$result[$i] = $result[$i] . $key;
$i++;
}
return $result;
}
Which provides this output:
array:6 [▼
0 => "apples"
1 => "bananas"
2 => "cherries"
3 => "dates"
4 => ""
5 => ""
]
But the 5th line needs to be "apples", the sixth needs to be "bananas".
Then on first line after "apples" needs to have "cherries", and so on, as in the example above.
Hope this provides clarification.

Answer 1

If I understand your question correctly, I think I have a solution.
I added the $n to the arguments list rather than defining it inside the function.
function makeArray($commonWords,$n=6){
$result = array_fill(0,$n,'');
$c = 0;
// while we still have words to print out
while(array_sum($commonWords)){
foreach($commonWords as $word=>$number){
// if this word is still available
if($number > 0){
// put the separator if we have looped through at least once
if($c >= $n){
$result[($c % $n)] .= ", ";
}
$result[($c % $n)] .= $word;
// reduce the number of this word available
$commonWords[$word]--;
$c++;
}
}
}
return $result;
}

Answer 2

It is not really clear what you are trying to accomplish, but you can do the following.
What you are describing here
But the 5th line needs to be "apples", the sixth needs to be
"bananas".
is Circular Linked list. But as the number of iterations cannot exceed the sum values of given array, this is somewhat circular linked list with a limit. You can read about Linked Lists in the wiki.
Luckily PHP has SplDoublyLinkedList class in the Standard PHP Library. But we have to shape it a little to serve our needs:
class CircularLinkedListWithLimit extends SplDoublyLinkedList
{
protected $limit;
public function __construct($limit)
{
$this->limit = $limit;
}
public function next()
{
$this->limit -= 1;
parent::next();
}
public function valid()
{
return $this->limit > 0
? parent::valid() || $this->rewind() || true
: false;
}
}
Having this class we can create our list:
$array = ["apples" => 4, "bananas" => 4, "cherries" => 4, "dates" => 3];
$limit = array_sum($array);
$list = new CircularLinkedListWithLimit($limit);
foreach ($array as $key => $_) {
$list->push($key);
}
Having this circular list we can populate our table (I hard coded $n here for the sake of simplicity, but you can wrap this in function):
$n = 6;
$i = 0;
$j = 0;
$table = array_fill($i, $n, []);
foreach ($list as $item) {
$table[$i][$j] = $item;
$i += 1;
if ($i >= $n) {
$i = 0;
$j += 1;
}
}
Having this table, you can do what you like. As you provided somewhat of expected output, here is code that will print it:
echo implode(PHP_EOL, array_map(function ($row) {
return implode(', ', $row);
}, $table));
This will result in
apples, cherries, apples
bananas, dates, bananas
cherries, apples, cherries
dates, bananas
apples, cherries
bananas, dates
Here is working demo.
As you can see almost all we do is using built-in functionality, bootstrapping it with simple non-nested loops to suit our needs. This is actually the goal of programming on high-level programming languages. Because the less code you write yourself, the fewer bugs you introduce into the system.